The technology of regional control for backlight involves the backlight brightness adjustment and corresponding pixel compensation according to the image content of the region to be displayed without losing any image brightness, which effectively save the power consumption and increase the contrast ratio. The brightness of LCD backlight may be adjusted by modes of zero-dimension, one-dimension and two-dimension, and the lighting source may be located at direct-emitting type and side-emitting type. The light-adjusting technology in two-dimension mode for light source of direct-emitting type is to divide the screen into several horizontal and vertical regions with independent light-adjustment, which can facilitate image compensation point-by-point upon the light source is reduced in brightness, thus it obtains most attentions of current studies and researches. As a contrary, the backlight of side-emitting type according to the prior art usually cooperates with light-adjustment technology in zero-dimension mode, due to its relatively broader diffusion range (as shown in FIG. 1) which makes the image compensation difficult.